Broaching fixture



3 1934- c. J. HALBORGi BROACHING FIXTURE Filed Feb. 25. 1951 2Sheets-Sheet l I n, I 1 m1 3 x m c J INVENTOR Carl J flalfiozy ATTORNEYs.

Oct 30, 1934. c. J. HALBORG BROAGHING FIXTURE Filed Feb. 25. 1931 2Sheets-Sheet INVENTOR Carl J. fialkor gz,

'35 are cut diagonally to the sides and the segment the structure shownin Fig. 8,

Patented @et. 3@, W342 U ED STATES PATENT orifice BROACHING rm'rnnc CarlJ. Ilalborg, Detroit, Mich, assignor to Colonial Breach Company, acorporation oi Michigan Application February 25, 1931, Serial No.518,063

1 Claim. (El. 90-33) My invention relates to breaches and broaching Afurther object of my invention is to provide fixtures, and particularlyto a'broaoh and fixture a broaching cutter, for machining teeth in'the,for cutting gear teeth and the like. periphery of an element, that isbuilt up from a The machining of spur gears is usually accomplurality ofmembers having cutting edges, which plished by mounting a plurality ofthe gear blanks conform with each other to effect a teeth cutting 66together and cutting the teeth in the periphery contour. thereofsimultaneously by a milling or like operas A still further object of myinvention is to protion. Such mass production entails considerable videanlachine for cutting teeth in a gear, which is expense in time, laborand equipment and when simple in construction, economical of manufaclothe teeth of the gears are disposed diagonally to ture, and which iscapable of'cutting teeth oi on its sides further time and expense isentailed in either the spur or helical type in a single operthemachining operation as each gear must be ation.

machined individually. Numerousother objects and features of novelty Ahelical gear is an example of one having teeth of my invention will heeither specifically pointed diagonal to its sides and when such a gearor out or will become apparent when referring, for to segment is to bemachined, the blank or segment a better under ndi o y v fl 110 must bemounted individually on an integrating following description inconjunction withthe achead which rotates the gear or segment inrelacompanying drawings wherein: tion to the teeth of the cutter whichare moved Figure 1 is a plan i w f a breaching cutter laterallythereacross. It is very apparent that a embodying features of myinvention, is gear or segment of this type is considerably more Fig. 2is a side view, in elevation, of 'the cutter expensive to machine,requiring additional appashown in Fig. l, ratus, time and labor, incomparison with the Figs- 3, l; 6. 5 o v enlarged, S s massed machiningof the spur type of gear. transverse sectional views of the structureshown In practicing my invention, I am able to conin Fig. '2, takenrespectively on the line 3--3, en siderably reduce the time, labor andexpense re- 4-4, 5-5 and 66 thereof.

. quired to machine a helical gear segment, by pro- Fig. '7 is afragmentary sectional view of the viding a machine in which the segmentis supstructure shown in Fig. 5, taken along the line ported and theteeth out therein by a single oper- 7-7 thereof,

ation of a cutter. I employ a machine having a Fig. 8 is an end view, inelevation, of a gear reciprocable operating mechanism, which drawssegment as machined by my cutters, the cutters directly across theperiphery of the Fig. 9 is a broken plan view of the structur segment tobe machined and by having the segshown in Fig. 8, ment disposed at anangle to the cutter the teeth Fig. 10 is a broken side view, inelevation, of

- 90 is provided with the helical type of teeth. Figs. 11, 12 and 13are, respectively, end, side I prefer to employ a built-up broachingcutter, and plan views of a. gear segment, similar to the having a bodyportion in which a plurality of elegear segment shown in Figs. 8, 9 and10, with the ments are disposed and retained in predetermined exceptionthat three teeth are cut thereon by a fixed position, having cuttingedges of such shape broaching cutter embodying a. modified form of 95and conforming with each other in such manner, my invention, as toprovide a cutting contour which produces Fig. 14 is.a view, partly insection and partly in teeth-like projections on the periphery of theelevation, of a. gear segment shown in Figs. 11, 12 segment i and. 13and of a breaching cutter embodying a Accordingly, one object of myinvention is to modified form of my invention, I e 10.

provide a machine, having a. reciprocable broach- Figs. 15, 16 andl'?are respectively plan, face ing cutter which is drawn once across theperiphand side views of a broaching fixture embodying cry of a segmentto machine teeth therein, features of my invention,

Another object of my invention is to provide Fig. 18 is a sectional viewof the structure shown a holder for a segment, in theperiphery of which'in Fig. 16,. taken along the line 18-18 thereof, 10.

teeth are to be cut in the above described manand v a ner, having meansfor retaining the segment at Fig. 19 isa broken sectional view, inelevation, of an angle to the cutter which thereby machines a breachingmachine embodying features of my teeth which are angularly disposed tothe sides invention. 0f the Segment, which are of the helical ypReferring more particularly to Fig. 19, my in- .11.

vention comprises in general a machine provided with a cradle 21, thefront end of which is supported on the standard 22, the rear end ofwhich is supported on a base portion (not shown) The cradle 21 isprovided with side rails 23 upon which a head 24 is mounted forreciprocable movement and from the front of which a pull bar 25 extendsthrough a face plate 26.

A suitable reciprocable operating mechanism (not shown) is connected tothe head 24 through a. rod 27 by which the reciprocable motion istransferred to the head 26 and pull bar 25. Suitable controlling means28 is provided, associated with the cradle, for the purpose of effectingthe reciprocation of the head 26 when the operating mechanism isregulated thereby. A suitable liquid and chip receiving pan 30 issupported on the standard 22, and is provided with a drain conduit 31,from which the liquid is screened and drained into a reservoir (notshown).

. A suitable work retaining and cutter guiding chuck 34 is supported onthe face plate 26, by bolts 35, through which the pull bar 25 extendsfor receiving a cutter 36 for the purpose of drawing it through thechuck 34.

Referring more particularly to Figs. 15, 16, l? and 18, I have shown thechuck 3 as comprising a body portion 3'?! having flanges 38 in which thebolt-receiving holes 39 are provided for the purpose of mounting thechuck on the face plate 26 as above described. A laterally disposedchannel a1 is provided in the body portion in which jaws 52 and is areretained, the latter by means of bolts i i. The engaging ends of thejaws are provided with sloping faces and 46 respectively and are biasedfrom each other by springs 47 which are disposed between the jaws. Anoperating block 49 is mounted in the channel 41 adjacent to the jaw 42,which is actuated by a cam 50, for movement longitudinally within thechannei.

Lugs 51 are provided on the side'of the body portion 37, through which ashaft 52 extends and which may be rotated therein by an operating handle53 provided on its upper end. The-cam 56 is retained in. fixed positionon the shaft 51 by a pin 54 and when the handle 53 is revolved the camis rotated to move the operating block 49 inwardly to force the jawsinto firm relation with a member. When the handle 53 is moved in anopposite direction, the cam releases the block 49 and the springs 47move one portion of the jaws and therefore the operating block 49,outwardly in the slot 41 for the purpose of releasing the clampedmember.

An aperture, 55 is provided through the center of the body portion,longitudinally thereof having guide plates 56 mounted adjacent theretoon the front of the body portion 37 by bolts 5'7, for preventingthe-lateralmovement of the broaching cutter 36, relative to the chuck.

' Asuitable plate 59 is provided in the aperture 55, a'cross the'uppersurface of which the broach-r ing cutter 36 is drawn by the pull bar 25.The

' lower surface' of the, plate 59 is sloping, as shown in Fig. 17',which registers with the oppositely sloping surface on a plate 58,disposed therebelow. The. plates 58 and 59 are clamped together in fixedposition by bolts 60 after the plate 59 has been adjusted laterallyrelative to the plate 58.

- To effect the adjustment of the plates 58 and 59 relative to eachother, i have provided an ad justing screw61 which engages threads inthe front surface of the plate 58 and'which is provided with anenlarged, cylindrical shaped head 62,

revenue the upper portion of which registers with a slot 63, provided inthe under side of the plate 59. When the head 62 is rotated to have thescrew 61 drawn inwardly into the plate 58, the plate 59 is movedtherewith, through the engagement of the head 62 with the slot 63 in theplate. The inward movement of the plate 59, relative to the plate 58,effects a fine vertical adjustment for raising or lowering the breachingcutter relative to the work piece.

The work piece 65 is more clearly shown in Figs. 8, 9 and 10 as beingasegment of a gear 66 provided integral with a spindle 67, the segmentand spindle being a portion of the steering mechanismof an automobile.It is to be understood that my machine is not limited to cutting helicalteeth or to machining this particular type of work piece as it is veryapparent to anyone skilled in the art that, by changing the chuck 35,other types of gear segment may be supported to have teeth out nor rnalor at any angle, .to the sides of any gear segment.

As shown in the figures, teeth 69 are provided diagonally to the sidesof the segment and are therefore of the helical type which, as pointedout hereinabove, is considerably expensive to pro vide because each gearor segment must be ma chined individually. Referring again to Figs. 15and 16, it will be'noted that the faces .5 and on the jaws 42 and &3 aredisposed at right angle 1 to the front surfaces thereof which are inangularly disposed relation to the body portion 3'7 of the chuck. Anaperture 71 is provided in the body portion 37, as shown in Fig. 15, inangular relation to its front surface for the purpose of receiving thespindle 67 when the front portion thereof is clamped between the jaws.

A suitable engaging screw 64: is mounted on the side of the operatingblock 49, by means of the threaded boss 68, having a clamping nut 76 'ofa work piece, is then inserted through the jaws until the rear surfaceof the segment 66 engages the front surface of the jaws. The-segment isdrawn over and retained against the adjusting screw 64 and the handle 53is then revolved in a clockwise direction to have the cam 50 thereonforce the operating block 49 laterally against the jaws, to cause themto close in upon the work piece. During this movement the segment66isadjusted relative to the cutter, by the adjusting screw 64 and thespindle 67 is firmly, clamped between the surfaces 45 and 46 of thejaws.

The breaching cutter 36 is then drawn rearwardly of the machine throughthe actuation of the operating mechanism, when energized through themovement of thehandle 28, in, a

wellknown manner and, after the breach has moved to its, rearwardposition, the teeth have deep, the adjustment of the plates 58 and 59,rela-,

tive to each other, are made in the above mentioned manner andthereafter teeth of theproper CJI I oraine height will be cut in theperiphery of the segments by the subsequent machine operations. Themachine is then reciprocated to have the breaching cutter extendfrontwardly of the chuck as shown in Fig. 19, and a new gear segment isthen inserted in the chuck and the operation repeated.

Referring more particularly to Figs. 1 to 7 inclusive, the broachingcutter 36 employed with my machine will now be described in detail. Abody' portion 72 is provided with. a pull-rod engaging end '73 havingrecesses it by means of which the brooch is engaged and drawn by thepull bar through the clamping fixture or chuck'34. The center of thebody portion is cut away to provide a channel-lilac structure, as shownin Figs. 3 to 6 inclusive, having a bottom web 75 and two upstandingflanges 76 of considerable thickness to provide strength to the bodyportion.

Cutting bars are mounted in the channel, thus formed, and, as shown inFig. 3; the frontmost bar 77 is of the same width as that of the channeland is provided with teeth 78 which extend slightly above the flanges'76. It will be noted that the first few rows of teeth '78 are solidtransversely of the bar which machines the peripheral surface of thegear segment 66 to form the top surface of the gear teeth. The rearmostteeth 78 are provided with aligned indentations of increasing depth 79,shown in Fig. 3, which conform to the uppe? and of the teeth on thesegment, the periphery oi the segment adjacent to the teeth is cut awayby the upstanding portions between and on either side of theindentations.

Adjacent to the rearward end of the .bar 7'7, a second section 80comprising three cutting bars as shown in Fig. 4 is provided of a lengthsubstantially the same as that of the cutting bar 7'7. The section 80comprises a central bar 81 and two cooperating side bars 82 which areretained in the channel of the body portion 72 by bolts 83 and projectfrom above the flanges 76 a greater distance than the teeth 78 of thebar 7'7.' The teeth are provided on the individual bars in progressingheights and widths, in such manner as to constitute with the teeth ofthe adjacent. bar, indentations of a contour exactly opposite toiithatof the teeth. to be cut in the segment 66.

Adjacent to the section 80, a third section 84 is provided which isshown in section in Fig. 5, as comprising three bars similar to theaforesaid bars shown in Fig. i but of greater height to provide agreater depth therebetween and which conform to the contour of the teethto be out. Adjacent to the rear end of the section 84- a fourth section85 is provided which is similar to the sections 32 and 83 with theexception that the indentations between the bars thereof more clearlyresemble the teeth to lee-cut so that the indentations at the end of thesection are provided with a contour which is exactly opposite to that ofthe teeth to be machined in the segment 66.

It is to be understood that, the indentations '19 in thesection '77 andthose provided between the various bars in the sections 82, 83 and 84,progressively increase in width and depth from the front to the rear endor the bar in substantially equal.

steps to providea breaching cutter which machines away the peripheryofthe sector 66 in substantially equal amounts throughout the length ofthe cutter. In Fig. '7, l. have shown a longitudinal sectional they arecut by the particular cutting edge. The chips are removed each time thebroach is drawn across the periphery of a segment, by a blower or othersuitable means, to prevent the clogging of the teeth. In Fig. 14, Ihave, shown the broach as being mounted with the teeth projectingdownwardly, in which construction, the cuttings fall from the teeth bygravity and no additional means need be employed for efiectingtheirremoval.

tapered slot 89 is provided in the body portion 72 in which a wedgingmember 97 is mounted for retaining the various sections ofthe cuttingbars in rigid longitudinal relation with each other. The holes, in theweb 75 of the body portion, for the bolts 83, are slightly elongated topermit the longitudinal movement of the bars.

Rearwardly of the wedging member 97 a member 98 of T-shape is pivoted ona pin 99 in such manner as to'be biased upwardly by springs 100. Themember is provided with a sloping surface 101 which is engageable by theends of the teeth 69 as the bar is drawn thereacross and a surface 102is provided in the plane of the segment, adjacent to the slopingsurface. After the segment has been released in the jaws by the movementof the handle 53, the return movement of the bar causes the surface 102to engage the teeth 69 of the segment to withdraw the segment from thelaws.

In Figs. 11, 12, i3 and 14 I have shown a work piece which is similar tothe work piece illustrated in Figs. 8, 9 and 10 with the exception thatthree helical teeth are cut in the sector thereof. A breaching cutter91, for machining the sector 90, is similar to the breaching cutter 36,having a body portion 92 which is centrally recessed longitudinally ofits length in a manner similar to that described above with relation tothe breaching cutter 36. A plurality of cutting bars 93, 9%,. and 9d areprovided with cutting edges which are related to each other in a mannersimilar to that described above, with the exception that a third recessis provided longitudinally of the cutter 91 for the purpose of machininga third tooth in the work piece 90.

The cutting bars 93 and 96 are provided with cutting edges throughouttheir depth forthe pur-- .on the body portion 92 of the cutter.

It will thus be seen that I have provided a machine ior cutting helicalteeth in a sector by a:

single longitudinal movement of a cutting tool. While- I haveillustrated and described helical teeth specifically, it is to beunderstood that. straight teeth similar to spur teeth. or the like maybe cut in a gear segment by merely changing the angular relation of thesector with the cutter.

The cutter employed for machining the teeth is .built up from a.plurality-of bars having cutting teeth along their periphery .whichareassembled newness Having thus described my invention, I claim: I

A machine for breaching teeth on a gear segn ent having a shank andincluding s reciproceble member, a branching cutter engageable by saidmember and hsving a, plurality of rows of wet/h thereon, ism forreceiving said shank and supporting said segment in the vicinity of andeat an angle to said member, and adjustable means for positioning saidsegment about the axis of said shank and relative to said member.

' CARL J. HALBORG

